Telephone calling dial



C. C. M CAIN TELEPHONE CALLING DIAL May 10, 19 49.

5 Sheets-Sheet 1 Filed Feb. 4, 1947 ATTOR/VF) May 10, 1949. c. c. MCCAIN TELEPHONE CALLING DIAL 3 Sheets-Sheet 2 Filed Feb. 4, 1947 Ill llll MI V5 70/? c. 6. Me 634/ C. C. MCCAIN TELEPHONE CALLING DIAL May 10, 1949.

Filed Feb. 4, 1947 5 Sheets-Sheet 5 Patented May 10, 1949 UNITED STATES PATENT OFFICE Cecil '0. McCain, Glen Ellyn, 111., ass'ignor to Western Electric Company, Incorporated, New York, N. Y., a corporation of NewYmk Application February 4, 1942?, Serial No. $126,256

"6 Claims. "1

This invention relates to telephone calling devices and more particularly .to dial Ltype telephone calling .devices commonly used in automatic telephone systems.

An objectof this inventionis to provide a telephone calling device of improved construction.

A particular feature-of the invention is the .provision of a one-way driving connection between the dial and .a spring driven, governor-controlled drive wheel of the ;pulsing mechanism, which driving connection permits the dial to positively rotate the drive wheel in unison therewith when the dial is rotated inone direction to dial a-digit and which permits .a faster rotary movement of the dial relative to .the governor-controlled spring actuated drive w'helina reverse direction.

Another feature provides for locking the dial in its starting position when the dial has been manually returned to that position in advance of the return to its normal starting position of the drive wheel of the pulsing mechanism and provides means for rendering the locking means inefie'ctive upon "the return to .its normal starting position of the drive wheel of the pulsing mechanism.

A "further feature of the invention provides means for adjusting the motor spring to varythe torsional force applied to the drive wheel and whichadjustingm'eans is accessible upon the removal ofth'e dial soth'at the torsional force may bein'creased or decreased from the front of the calling device after the dial has been removed.

Theseand other features of the invention will hemore iullyunders'tood from the "following description thereof when considered in connection with the accompanying drawings illustrating a preferred embodiment of'the invention in which Fig. '1 is .a front elevational view of a calling device;

Fig. 2 is an "enlarged rear elevational view of calling device in which the pulsing contact springs .and the cam "for actuating same are shown in one :position;

3 and 4 are detailed viewsof the pulsing contacts and the actuating cam shown in different positions;

Figs. 5 and 5 .are vertical sectional views through the calling device taken on the lines 5-5 and 5- 6, respectively, of Fig. 2;

Fig. 7 is a detail plan sectional view through the device taken on the line 1-7 of Fig.

Fig. '8 is a fragmentary elevational view of a portion of the device showing the governor for controlling the rate of -'pu'lse transmission;

Fig-9' is an "enlarged detail sectional =view 'o'f the pulsing contact springs ,and the actuating mechanism thereof as viewedirom the front and taken ontheline 9-4! ofFig. 6.;

Fig. 10 is a vertical sectional view of the device taken on the line |.ll.ll] of Fig. 5 showing the .device with the number .plate removed and in which members, comprising the driving connection between the dial and the driving wheel, are shown .in their normal or starting position and with astop and-a latching member associated therewith;

Fig. .11 is a :detail plan sectional view showing the driving connection between .the dial and the rotatable .drive wheel taken .on the line I l-ll of Fig. 1'0;

Figs. 12 and 13.are detail views of a portion of the device illustrating various positions of the members comprising the driving connection 'between the dial .and the wheel and their relation to the stop and latching .members associated therewith;

ZFig. 14.15 .aQfragmentary vertical sectional view of the device taken on .the'line "I'd-14 of Fig. 5 and in which .is shown the means for adjusting the spring to vary the tension on the wheel; and

Fig. '15 is 'a detail sectional viievv taken on the line "iii-15 of Fig. '10 showing the spring adjusting members.

The calling device as "illustrated in the drawings, particularly Figs. "2, 5, 6 and 10, comprises generally a housing or casing 29 having a centrally disposed bearing member 22 fixed thereto for rotatably supporting a finger wheel ord'ial 2 and .a driving wheel 2B of "a gear train, which wheel is stressed for rotation in a counter-clockwise direction, as viewed from the front by a torsion motor springZfi. The dial 2% is operatively connected to the driving "wheel '25 through a driving connection 30 "(Figs "5 and 11), which permits the imparting of rotary 'movement to the driving whel bythe :dial upon rotationin a clockwise direction and permits of a relative faster movement of the dial with respect to the driving "wheel on the reverse movement thereof. The :gear train is connected to 'a governor shaft 32 (Figs. 10 "and T1) for'actuating a governor are and to 'a jack "shaft "3'6, on which is mounted actuating means "38 for actuating the pulsing contact springs 41] and 41.

The housing!!! has'acylindrical 'wall 42 (Fig. 5) projecting -from a fiat wall "'33, which is centrally apertured to receive the bearing member 2'2,which,"ln turn, has aiiange lt fastened tothe wall 48 of the casing by rivets 45 tosecure the bearing member 22 in position on the casing 20. The bearing member 22 is apertured at 46 to receive and rotatably support a shaft 41 having a flange 48 against which the dial 24 is positioned and which has non-circular portion 49 engaging in a similarly shaped aperture 50 in the dial. The dial 24 is locked on the shaft 41 by a nut engaging the reduced threaded end 52 of the shaft with a Washer 53 interposed between the nut and the disc. An arm 55, secured to the other end of the shaft ll by a nut 56, serves to retain the shaft in the bearing member 22.

The driving wheel 26 comprises an annular gear 60 (Fig. 5) secured to ahub member 6!, which is rotatably mounted on the exterior bearing surface 62 of the bearing member 22 and retained thereon against longitudinal movement by a shoulder 63 and a split retaining ring 64 fitting in an annular groove E5 in the bearing member 22. A pin 68 (Figs. E i and 15) extending rearwardly from the Vertical face of the hub member 6i, engages in one of a plurality of apertures 69 of an annular adjusting member '10 rotatably mounted on the bearing member 22 in engagement with the hub member 6|. An ear 'H (Figs. 5 and 14), formed on the adjusting member 10, engages one end "d2 of the torsion motor spring 28, the other end '53 of which is anchored to the flange id of the bearing member 22. The spring 28 exerts a torsional force on the member and the driving member 26, tending to rotate them in a counterclockwise direction, as viewed from the front, and the spring 28 is set under a predetermined initial tension. This tension can be adjusted by removing the dial 24 (Figs. 2 and 10) and inserting a tool through an arcuate aperture M in the hub member iii into engagement with one of the apertures 69 of the adjusting member iii accessible through the aperture I4 and moving the adjusting memher axially to disengage it from the holding pin 68 and then rotating the member iii to a position where the holding pin 23 is in alignment with the next aperture 89 and then allowing the spring 28 to move the adjusting member la] axial- 1 ly into engagement with the hub member 6i and with the holding pin 68 engaging in another of the recesses 69. In this'manner, the member 10 may be rotated step by step in either direction relative to the drive wheel 26 until the tension of the spring 28 has been adjusted to the desired amount.

The clutch or driving connection 3t (Figs. 5, l0 and 11) between the dial 2% and the driving wheel 26 comprises a driving member or pin 18,

which is semi-circular in cross section and extends rearwardly from the flange 18 supporting the dial 2 2- and engages on its flat side '19 a pin 80 on the hub member 8 i. The spring induced rotary movement of the drive wheel 22 in a counterclockwise direction is transmitted by the pin 80 to the pin 78 and the dial 24 and is arrested when the dial 25 and the wheel26 are in a predetermined position by the engagement of the pin 18 with a stop member 82 fixed to an annular supporting member or plate 83. The annular supporting plate 83 is mounted onthe wall 63 of the housing 20 in spaced and parallel relation thereto by the arms 84 and screws 85. With this construction of drive connection between the dial 24 and the driving wheel 26, the dial may be rotated through a dialing movement in a clockwise direction, as viewed in Fig. 1, to impart a positive rotation through afsimilar arc to the driving wheel 26 and the drive connection permits of a faster rotation of the dial relative to the driving wheel 26 in a counterclockwise direction. After a dialing movement in a clockwise direction of the dial 2d, the dial may be manually returned to its starting position at a greater speed of rotation than that of the governor-controlled rotation of the driving member 26 without effecting the normal operation of the drive wheel 26 To prevent the dialing movement of the dial 2 1 to initiate another digit dialing operation before the completion of the pulsing operation of the previous digit dialing operation, a latching means is provided and comprises a spring wire 88 (Figs. 1G and 11) anchored at 89 to the supporting plate 83. The end 90 of the member 88 is normally positioned in the path of movement of the pin '58 on the dial (Fig. 13) and, by engaging the flat surface 79 thereof, prevents rotation in a clockwise direction of the dial 2 1. The latching member 83 is engaged by the pin 80 on the wheel 25 and is displaced downwardly thereby to disengage the end 9% from the pin 19 when the driving wheel 26 returns to its normal starting position on completion of its pulsing cycle. With the drive wheel 26 and the pin 8!] carried thereby in their normal starting position, the latching member 33 is ineffective to latch the dial 2% and the dial may be rotated in a clockwise direction to initiate a new dialing operation.

The gear 68 of the driving wheel 2t meshes with a pinion gear on the ac shaft 35 (Figs. 6, '7, 1i) and 14), to which is secured a gear 94, which meshes with the pinion gear rotatably mounted on the governor shaft 32. The governor shaft 32 has one end thereof mounted in a bearing t l (Figs. 5 and '7) carried by the supporting plate 83; and the other end mounted in a bearing 98 of the governor housing Q9. A hub we (Fig. 7) of the gear 95 receives a clutch member comprising a closely wound helical spring H32, which also engages a peripheral surface of the hub IE3 secured to a cross arm I64 of the governor 34. The cross arm it has pivoted thereto, as on pins ill5lfi5, a pair of weight members lfifi-IOE, which are maintained in normal retracted position by springs lilllfill and which carry friction shoes i i8ii38 engageable with the inner surface of the drum iilil of the governor housing Q9. The spring clutch member I62 permits the free rotation of the gear 95 in one direction and serves to connect the governor 32 to the gear 95 upon rotation of the gear in a reverse direction. Thus, the driving wheel 25 is disconnected from the governor 34 during its movement in a clockwise direction and is free to be rotated in a clockwise direction at any speed imparted to it by the dialing movement of the dial 2 3 and is effectively connected to the governor 34 upon its rotation in the reverse direction so that, as it rotates in a reverse or counterclockwise direction, its speed is controlled by the action of the governor 34. The dial, however, as previously mentioned, is free to be rotated at a faster speed if desired in a counter-clockwise direction to its normal starting position.

The jack shaft 36, which is rotated in response to the rotation of the drive wheel 26, is mounted in bearings H5 and H6 (Figs. 6 and '7), the former carried by the supporting plate 83 and the latter provided in a bracket H7 formed on the wall 43 of the housing 26. The pulsing or actuating means 38 (Figs. 3 and i), mounted on the shaft 36, comprises a cam I l8 fixed to the shaft, the cam having a pair of diametrically opposed actuating lobes Ila-.1- I9: The cam ms, engages;

a. hub portion 12 i, is loosely mounted on the.

shaft 36 between the cam H8 and an enlarged portion I25. of the shaft 36. Extending radially from: the hub portion I24; and-in angular relation to; each other, are arms, I26. and I21 (Fig. 9). A spring friction member [28, mounted on the arm i2i by a. pin I219, engages the enlarged portion. I25 of the shaft 36 in: a groove I39 therein. and.

frictionally connects the fly member I23 to the shaft (iii fOrrotation therewith. The rotation of the fly member in. one direction, is limited by the engagement of the arm I26 with; the bracket.

iil (Fig. 3) and the rotation of the fly member in the other direction is.- limited by the. engagement; of, the arm I21 with the governor housing 95. (Fig. 4). As the. Shaft. 36. is rotated in the direction indicated by the arrow in Fig. 4, the fly member will be moved to the position shown in said Fig. 4 with the arm; I26; projecting toward the contact spring member: 4d: and in the path of a laterall extending tab. or extension I33 thereon (Figs. '7 and 9) so that, as the cam IIB continues to rotate and the contact springs 4i and it follow the cam to the. right, as viewed in Figs. 2 and 4, the arm I126. will serve to stop the contact spring it after ashort movement thereof and permit the separation of the contacts 42! and t! as the member I261 rides off of the lobes H9 of the cam onto its low portions. Thus, while th shaft 36 is rotating in the direction indicated by the arrow in Fig. 4, the arm I25 of the fly memher 523 and the cam H8. cooperate to effect the opening and closing of the contact springs 42 and M twice for each revolution of the shaft 36. When the shaft eels rotated in the opposite direction, that is, in the direction indicated by the arrow in Fig. 3, the fly member I23 is rotated to the position shown in Fig. 3, where the arm H26 thereof has been moved out of the path of the contact spring 40, thereby permitting the contact springs to and. M to remain in contact with each other and move together through the oscillatory movements imparted to them by the cam HS. Thus, during the dialing movement of the dial and the driving wheel 2%, that is,

clockwise rotation, as viewed from Fig. 1, the fly member I23 acts to render the pulsing means ineffective and during the movement in a reverse direction of the drive wheel .28, the fly member serves to render the pulsing mechanism effective to produce pulses in response to the actuation of the contact springslifl and-4| by the cam HE.

A pair of normally open contact springs I38 (Fig. 2) and a pair of normally closed contact springs 137, actuated by a roller I38 on the arm 55 of the shaft ii in response to the dialing movement of the dial 24, are molded. in the terminal block 522 and are connectible in the conventional manner to the substation apparatus for disconnecting the receiver and shunting the transmitter during th dialing. operation.

An annular number plate I40 (Fig. fitting within the annular wall 42. of; the housing 20, forms. a cover plate for the. calling device and engages the supporting plate: 8.3; and is. locked in:

positiontheir-elmv by a split retaining ring, I-4I- fitting in an annular groove-an; annular fla e; 142 formed on the innezrllortionotthesupporting plate 83. Within the. annular flange I42,,the annular space I 43. surrounding the; bearing 22 provides a clearance for-themovement of the drive pin it on the flange: 48; of; the shaft 41; and also providesclearance forthe. insertion of atool for engaging the spring adjusting; member It for the purpose of adjusting, thetension of the spring when the dial 24 has been. removed. Numerals. or other indicia M5 (Fig. 1); is printed or otherwise formed on the number plate Mil in predetermined position angularly spaced-about the axis: of the dial and, in alignment withv finger holes: 54? formed in the dial 24-. Av stop Hi8: overlying: the dial. 2% is carried. by the housing 2E! and servesto engage the finger: of the person calling and. limit the dialing-movement: of thedial 24..

When dialing a number, as. for example, the digit 9, the party calling inserts his finger in; the finger hole I41 of the dial. 2% opposite the. numeral 9 and rotates thedial clockwise until his finger engages the stop I148, after which he re.- rnove-s his finger and: the dial is returned to its original starting position, as. shown in Fig. 1. As the dial 24. is rotated in aclockwise, direction during the dialing movement,.the drive pin it carried. thereby, through its engagement with the pin 89 on the drive wheel, imparts a. rotary movement to the drive wheel 26 equal. in length to and in unison with the movement of the dial 2d. The rotation of the drive wheel 26:oauses the rotation. of the cam shaft 36 and the cam H8 and the shifting of the fiy member I23 carried thereby and effects the movement of the pulsing springs 49 and iii. The rotation of the shaft 3.5 during the dialing movement of the dial 2 3 is in such a direction as to cause the fly member I23 to be moved into the position shown in Fig. 3, in which position'of the fly member I23 the pulsing springs 30 and iii are rendered inefiective and follow the contour of the cam I 18 and'are oscillated thereby with the contacts maintainedin engagement with each other. Consequently, no pulses are being produced during the dialing or clockwise movement of the dial 24. The rotation of the drive wheel 25 during the dialing movement imparts rotation to the governor shaft 2 through the gears 2t, 9t and {-35, which rotation of the governor shaft 32 is not transmitted to the governor because of the action of the clutch member I02, which, as hereinbefore stated, serves to transmit rotation to the governor only when the shaft rotates in the opposite direction.

At the end of the dialing movement, when the finger of the person dialing is removed from the dial, the motor spring 28 causes the drive wheel- 2 3 to be returned toits starting position and, through the engagement of thepin so carried thereby with the-drive pin 7I8 on the dial, the dial 24 is rotated with the drive wheel 25 to its normal starting position. During the counter-clock Wise movement of the drive wheel 25, the governor 3 i is connected to the-drive and serves to govern the speed of rotation and the rate of pulse transmission. The rotation of the shaft 26 during the return movementiof the drive wheel 26 is in the direction to cause. the fly member I 23.. carried thereby to be movedinto the position shown in Fig. 4% and acts to-hold-the pulsing spring ii! substantially in a fixed position so that the cam- H8, during therotationoithe shaft 35-, acts to reciprocate the contactspringll; into and output contact with the spring 40 and cause the production of a series of pulses.

Should the person dialing, at the end of a dialing movement, decide to manually return the dial 24 at an increased rate of speed substantially faster than that of the governor controlled move-- ment of the dialing wheel 26, with the intention of speeding up the dialing operations, the dial Ed is free to be rotated to its starting position without in any way afiecti ng the counter-clockwise rotation of the governor controlled drive wheel 2-8 of the pulsing mechanism. When the dial it, after first having been rotated in a clockwise direction, is rapidly returned to its normal starting position in advance of the driving Wheel 2 8, the drive pin it, rotating with the dial, engages the side of the latching member 88, moves it out of the Way as the pin 73 passes, and permits it to return to its normal unfiexed position with its end 96 in the path of and in substantial engagement with the face it of the pin l8, as indicated in Fig. 13. The latching member 33, in this position, serves to latch the dial 24 in its starting position until the pulsing portion of the cycle has been completed and the wheel 2-6 has returned to its normal starting position, during the final portion of the movement of which the pin 88 carried by the wheel 26 engages the latching member 88 and moves it out of its latching relation with respect to the drive pin 18. It will thus be seen that the dial 24, when returned to its starting position before the completion of a pulsing portion of the cycle of operation, is latched in its starting position and cannot be rotated to initiate another digit dialing operation until the previous pulsing cycle has been completed.

What is claimed is:

1. In a telephone calling device having pulsing contacts and means for actuating said pulsing contacts including a rotatable wheel, the com- .5:-

bination with said rotatable wheel of a bearin for rotatably supporting said wheel, housin means for substantially enclosing said actuating means and through which a portion of the wheel is accessible, an annular adjusting member encircling the bearing member and engaging a portion of said wheel, a motor spring encircling said bearing member for rotatin said wheel in one direction and having one end thereof fixed relative to the housing and the other end connected to the adjusting member, and means or; said adlusting member and said wheel for making an interlocking non-rotatable engagement of said adjusting member with said wheel in any one of a plurality of angular positions, said wheel having an opening therein through which said adjustable member is accessible whereby a tool may be inserted through the opening into engagement with said adjustable member to adjust it relative to the wheel.

2. In a telephone calling device having pulsing contacts and means for actuating said pulsing contacts including a rotatable wheel, the combination with said rotatable wheel of a bearing for rotatably supporting said wheel, housing means for substantially enclosing said actuating means and through which a portion of the wheel is accessible, an annular adjusting member encircling the bearing member and engaging a portion of said wheel, a motor spring encircling said bearing member for rotating said wheel in one direction and having one end thereof fixed relative to the housing and the other end connected to the adjusting member, and means on said adjusting member and said wheel for making an interlocking non-rotatable engagement of said adjusting member with said wheel in any one of a plurality of angular positions, said wheel having an opening therein through which said adjustable member is accessible whereby a tool may be inserted through the opening into engagement with said adjustable member to adjust it relative to the wheel.

3. In a telephone calling device having pulsing contacts and means for actuating said pulsing contacts including a rotatable wheel, the combination with said rotatable wheel of housing means substantially enclosing said actuating means and including a front wall having a central aperture therein, a removable dial on the outside of said housing operatively associated with said wheel and concealing said aperture in said front wall, bearing means carried by said housing means for supporting said wheel and said dial for rotation about a common axis extending through the aperture in the front wall, an annular adjusting member encircling said bearing means and axially movable thereon into engagement with said 'wheel, said r wheel and said adjusting member having interfitting portions whereby the adjusting member may be received in any one of a plurality of nonrotatable interlocking positions with respect to said wheel, and a motor spring for rotating said wheel in one direction and having one end thereof fixed relative to the housing and the other end connected to said adjusting member, said wheel havin an openin therein in alignment with the aperture in the front wall and through which the adjustable member is accessible when the dial is removed whereby a tool may be insorted through the aperture in the front wall and the opening in the wheel to engage and adjust the adjustable member relative to the wheel.

4. In a telephone calling device having pulsing contacts and means for actuating said pulsing contacts including a rotatable wheel, the combination with said rotatable wheel of a housing means substantially enclosing said actuating means and including a front wall having a central aperture therein, a removable dial on the outside of said housing operatively associated with said wheel and concealing said aperture in said front wall, bearing means carried by said housing means for supporting said wheel and said dial for rotation about a common axis extending through th aperture in the front wall, an annular adjusting member encircling said bearing means and axially movable into engagement with the rear face of said wheel, said adjusting member having a plurality of equally spaced apertures therein located equi-distant from the axis of rotation of said wheel, a pin on said wheel axially engageable in any one of said apertures in said adjustable member for locking said adjustin member on said wheel against rotation relative to each other, and a helical spring encircling said bearing means and having one end thereof fixed relative to the housing and the other end thereof connected to the adjusting member for rotating said adjusting member and urging said member into engagement with said wheel, said wheel having an aperture therein uncovering a plurality of apertures in the adjusting member whereby, when the dial has been removed, the adjusting member may be adjusted relative to the Wheel with the aid of a tool inserted through the central aperture in the front wall of the housing and the aperture in said wheel.

5. In a telephone calling device having pulsing contacts and means for actuating said pulsing contacts including a rotatable wheel have a wall portion, the combination with said rotatable wheel of bearing means for supporting said wheel for rotation about its axis, housing means including a wall portion for substantially enclosing said actuating means, a motor spring for rotating said wheel and having its opposite ends operatively connected respectively to the wall portions of said housing and said wheel, and tension adjusting means for said spring interconnected between one end of said spring and its cooperating wall portion comprising a member operatively connected to said one end of said spring and engageable with said cooperating wall and angularly adjustable relative thereto about said axis, said member and said cooperating wall being shaped to have interfitting portions whereby said member may be received in any of a plurality of positions angularly disposed about said axis and relative to said cooperating wall to form a non-rotatable connection therebetween, said cooperating wall having an opening therein through which said member may be engaged by a tool and adjusted relative to said cooperating wall angularly about said axis to vary the tension of said spring.

6. In a telephone calling device having pulsing contacts and means for actuating said pulsing contacts including a rotatable wheel, a combination with said rotatable wheel of a bearing for supporting said wheel for rotation about its axis, housing means for substantially enclosing said actuating means and having an opening through which the portion of said wheel is accessible, an adjusting member engageable with and adjustable about its axis relative to the wheel, means for guiding said adjusting member axially relative to the wheel, a motor spring disposed about said axis and having one end thereof fixed relative to the housing and the other end operatively connected to the adjusting member for urging said member into engagement with said wheel and 'for stressing said member for rotation in one direction, and means on said wheel and said adjusting member providing an interlocking non-rotatable engagement of said adjusting member with said wheel in any one oi a plurality of positions angularly disposed about said axis, said wheel having an opening therein through which said adjustable member is accessible whereby a tool may be inserted through the opening into engagement with said adjustable member to efiect axial movement and rotation of the member relative to the wheel to vary the tension of said motor spring.

CECIL C. MCCAIN.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,226,953 Dyson May 22, 1917 1,258,686 Kaisling Mar. 12, 1918 1,264,366 Clausen Apr. 30, 1918 1,444,777 Blessing Feb. 13, 1923 1,454,496 Vischer May 8, 1923 1,543,662 Booth June 30, 1925 1,662,141 Blades Mar. 13, 1928 2,252,875 Wheeler Aug. 19, 1941 

